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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
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 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
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package sun.tools.tree;

import sun.tools.java.*;
import sun.tools.asm.Assembler;
import sun.tools.asm.Label;
import java.io.PrintStream;
import java.util.Hashtable;

WARNING: The contents of this source file are not part of any supported API. Code that depends on them does so at its own risk: they are subject to change or removal without notice.
/** * WARNING: The contents of this source file are not part of any * supported API. Code that depends on them does so at its own risk: * they are subject to change or removal without notice. */
public class WhileStatement extends Statement { Expression cond; Statement body;
Constructor
/** * Constructor */
public WhileStatement(long where, Expression cond, Statement body) { super(WHILE, where); this.cond = cond; this.body = body; }
Check a while statement
/** * Check a while statement */
Vset check(Environment env, Context ctx, Vset vset, Hashtable exp) { checkLabel(env, ctx); CheckContext newctx = new CheckContext(ctx, this); // remember what was unassigned on entry Vset vsEntry = vset.copy(); // check the condition. Determine which variables have values if // it returns true or false. ConditionVars cvars = cond.checkCondition(env, newctx, reach(env, vset), exp); cond = convert(env, newctx, Type.tBoolean, cond); // check the body, given that the condition returned true. vset = body.check(env, newctx, cvars.vsTrue, exp); vset = vset.join(newctx.vsContinue); // make sure the back-branch fits the entry of the loop ctx.checkBackBranch(env, this, vsEntry, vset); // Exit the while loop by testing false or getting a break statement vset = newctx.vsBreak.join(cvars.vsFalse); return ctx.removeAdditionalVars(vset); }
Inline
/** * Inline */
public Statement inline(Environment env, Context ctx) { ctx = new Context(ctx, this); cond = cond.inlineValue(env, ctx); if (body != null) { body = body.inline(env, ctx); } return this; }
The cost of inlining this statement
/** * The cost of inlining this statement */
public int costInline(int thresh, Environment env, Context ctx) { return 1 + cond.costInline(thresh, env, ctx) + ((body != null) ? body.costInline(thresh, env, ctx) : 0); }
Create a copy of the statement for method inlining
/** * Create a copy of the statement for method inlining */
public Statement copyInline(Context ctx, boolean valNeeded) { WhileStatement s = (WhileStatement)clone(); s.cond = cond.copyInline(ctx); if (body != null) { s.body = body.copyInline(ctx, valNeeded); } return s; }
Code
/** * Code */
public void code(Environment env, Context ctx, Assembler asm) { CodeContext newctx = new CodeContext(ctx, this); asm.add(where, opc_goto, newctx.contLabel); Label l1 = new Label(); asm.add(l1); if (body != null) { body.code(env, newctx, asm); } asm.add(newctx.contLabel); cond.codeBranch(env, newctx, asm, l1, true); asm.add(newctx.breakLabel); }
Print
/** * Print */
public void print(PrintStream out, int indent) { super.print(out, indent); out.print("while "); cond.print(out); if (body != null) { out.print(" "); body.print(out, indent); } else { out.print(";"); } } }